Production of light sensitive photographic material



ESQ-G98 v; Patented Dec. 19, 19

UNITED STATES PATENT OFFICE asssjiis' PRODUCTION OF LIGHT- SENSITIVE PHOTOGRAPHIO MATERIAL.

WalthenKiihne; Mannheim, Germany; rested in the Alien Property Custodian No Dra'wing Application March 12,1940, Serial No.i.323,576. .InGermany February 25, 1939 5' Claims.

This;invention relages tothe production of light sensitive photographic material;

Light sensitive photographic material like plates, films, diazo printing foilssubstantially consists of a support and-alight sensitive emulsion layer mostlycomposedzof proteins, especiallygelatin, albumins etc. To use-proteins for the, production-otthc; supportis impossible on account-of their high water. sensitivity and insufficient mechanical, -strengtn, Nor are hard-' ened-gelatinioilssuitable. which are less watersensitive and mechanically stronger than un-. hardenedonesl They are forinstance not flexibleenough to be. .employ ed for motion picture films... On.the;.0ther "hand.a lightsensitive gelatin .layer' of greater. thickness and possessing the.

ent inventiontoprovidea method for the. production of lightsensitive photographic material to be charged WithJight. sensitive.v photographic compounds directly. andwithout .the application Still further objects 'Will'become' apparent from 1 the detailed specification following hereinafter.

It hasbeen found'that'sheets, foils and fabrics made from superpolyamides, i. e., high molecular condensation products resembling polypeptides, obtained for instance from diamines and dicarboxylic acids and their salts or from amino carboxylic acids and their lactams, may be easily charged with light sensitive inorganic and organic compounds without the use of an additional binding agent. Light sensitive compounds precipitable or adsorbable from aqueous solutions may be easily incorporated into the surface 5.;of films and filaments produced from superpolyamides or may be precipitated on them. The mechanical strength will not be weakened thereby and the exact measures of the registered images will be preserved.v It is .practical to use lowstretched, highly oriented sheets, foils and fabrics made of stretched filaments. It is also possible to first'incorporate the light sensitive compounds into the sheets and foils consisting of superpolyamides and then to stretch them. These stretched foils are also suitable as optical polarizers. For that purpose it is practical to dye them :with. dichroitic or substantive cotton dyestuffs before or afterith'e stretching whichcauses crystal orientation-like Kongo red, cellulose rayon black,. etc.

The isuperpolyamides chemically related to the proteins 1 combine in. themselves, so to speak, the properties'of thesupport hitherto used and ofthe'zwelleknown' binding. agents for-the light -'sensitive compounds. Nonfiammable, mechanically excellent single-.layer.motion picture films are obtained inthis way as well as printing foils fast to tear-and shrinkage. Awide variation is possible in the selection ofthe light sensitive compounds. It is possible to apply. silver halide salts usual in photography, furthermore chromium .and iron saltsfor chemographic and heliographic processes and also light sensitive organic v dyestuffs and their intermediatereaction products, for instance diazo compounds of p-diamines,

like N-phenyl-p-phenylene -diamine or p-N-dialkylaminoaniline. The superpolyamides absorb inanexcellent way. dyestufis from aqueous solutions andsuspensions, so'thatdifferent dyestufi classes, evensensitizers, may be applied. Most suitable are dyestufis. which are to be dyed in an acid orneutral bath and developed by an aftertreatment with complexand salt-forming means or fixed invany otherway. superpolyamid foils and fabrics may also be charged with diazo compounds which by coupling. with suitable components are rendered fast to light. Finally also leuco-suliuric acid esters of 'vat'dyes and'poly methine dyes may be used as sensitizers.

To charge the surfaces with light sensitive compounds, may be accomplished by a printing process, as for instance in cloth printing.

For the production of non-transparent photographic foils titanium white or other pigments 55 may be added to the superpolyamide used in the production of the foils, so that in the following printing process images on a white or bright colored back-ground are formed. Large sheetsand foils consisting of superpolyamides may thus be provided in a photographic manner with any pattern desired, for instance with a woodor marble design. Furthermore laminated sheets and foils and fabrics maybe built up of various superpolyamides in different stages of condensation in such a way, that the uppermost layer is made more capable of swelling, for instance in water, aqueous solutions and organic solvents than the middle layer- After introducing the light sensitive compounds the increased swelling properties may be wholly 15' or partly neutralized by an after-treatment, for

instance by hardening agents or theeffect 'of heat.

Example I A foil consisting of the polymerisate of epsilonaminocaprolactam is bathed 5 minutes in a 5 percent silver nitrate solution and after short washing again bathed 5 minutes in 5 percent potassium bromide. After drying this material can be printed and developed like ordinary photographic material and the silver image obtained plays the same role as silver has hitherto done in the ordinary photographic materials, chemically and physically, as final image and as intermediate image,for instance in the transitory stage of the color developing process, silver bleaching process, residual image and antidiazotate process. Such material may also be workedup according to the reversal process.

Example II A foil consisting of the polymerisate of epsilonaminocaprolactam. and containing a white pigment, for instance bariumsulfate or titanium dioxide is soaked 5 minutes in a solution of 5 percent potassium bromide and after short washing again 5 minutes in 5 percent silver nitrate solution. After drying the foils thus obtained may be printed like P. O. P. and may be fixed in the 4 usual way.

Example III Example IV Three foils consisting of the, interpolymerisate of epsilon-aminocaprolactam and p-aminobenzoic acid are dyed by imbibition each in one of the three primary colors for subtractive color reproduction and afterwards bichromatized according to Example III. By etching, as described in Example III, colored reliefs are produced and by superimposing these three reliefs in neutral colors are obtained.

Ea'ample V One or several dyestuffs suitable for the color bleaching process, for instance erythrosine,

auramine and methylene blue, if necessary together with a chemical sensitizer like thiosinamine are incorporated by imbibition into a foil consisting of the polymerisate of e-aminocaprolactam. The color images obtained in the usual way by bleaching and fixing may be used as multicolor transparencies or as prints after having been united with a light reflecting support.

Example VI A foil consisting of the condensation product of hexamethylenediamine and adipic acid is soaked in, a solution of 4 grams of the sodium salt of the sulfuric acid ester of leuco-4.4-dichloro-5.5'-dibromindigo, 4 grams cupferron (N-nitrosophenyl-hydroxylamine ammonium), cc. glycerol and 80 cc. water and afterwards dried. The vat dyestufi forms on the exposed places during exposure.

For photography in natural colors the leuco compounds of a yellow, a purple and a blue-green dyestuff are employed in separate foils.

Fixing is done by soaking 5 minutes in warm water at 70 C.

Example VII A foil of the condensation product of hexamethylenediamine and adipic acid is soaked in a light sensitive solution consisting of 2.l.4.-diazonaphtholsulfo acid, resorcin and nickel sulfate.

For protection against damaging the foils may be coated after drying prior to exposure or after development with a lacquer containing besides a cellulose ester and -ether a natural or synthetic resin and, if necessary, water-repellent substances like parafiin and softeners.

What I claim is:

1. A light-sensitive photographic material in the form of a layer of afilm-forming linear superpolyamide which is insoluble in water, shrink-resistant and capable of being charged 5 with a substance sensitive to light from an light.

2. A light-sensitive photographic material as claimed in claim 1 in which the light-sensitive substance is a silver halide. I

3. A light-sensitive photographic material as in claim 1 in which the light-sensitive substance is. a light-sensitive diazo compound.

4. A light-sensitive photographic material as in claim 1 in which the light-sensitive substance is a light-sensitizing chromic acid salt.

5. A light-sensitivephotographic material in the form of a stretched, highly oriented sheet, suitable as an optical polarizer, said sheet consisting of a film-forminglinear superpolyamide which is insoluble in water, shrink-resistant and capable of being charged with a substance sensitive to light from an aqueoussolution, said sheet containing in fine division in only the surface portion thereof a substance which renders the sheet sensitive to light.

WALTHER 

